耐盐碱植物牛角瓜产能成分分析

对海南产耐盐碱植物牛角瓜(Calotropis gigantean)产能成分进行了较系统的研究. 采用气相色谱-质谱联用仪(GC-MS)研究结果表明,牛角瓜汁液中含有C7~C44的烷烃,其中C21烷烃含量最高,占总烷烃的52.98%左右,C7~C17的烷烃占10.28%左右,C29~C44的烷烃占37.45%左右,汁液中总烷烃含量为0.02%~0.03%,整株中总烷烃含量为0.01%~0.015%. 按煤炭样品的国标分析检测方法检测牛角瓜灰分为8.10%,挥发分含量为68.90%,热值为17.93 MJ/kg,碳氢含量总和达到49.51%,高于已报道的印度白花牛角瓜的46.22%,硫含量仅为0.55%,综纤维素的含量以茎中最高,皮中最低,牛角瓜皮含油脂量最髙,在全株中多糖和蛋白质含量都较高,而在汁液中则含量较低.     

超声处理对红花籽油理化性质及脂肪酸组成的影响

研究了不同超声条件下,红花籽油过氧化值、酸值、皂化值及脂肪酸组成的变化规律。结果表明:超声温度控制在50℃以下,超声功率小于等于600 W,超声时间短于60 min时,超声处理对红花籽油的过氧化值、酸值无明显影响,当超声功率高于600 W时,过氧化值、酸值随超声时间的延长而增加;超声温度控制在50℃以下,超声功率小于等于900 W,超声时间短于60 min时,超声处理对红花籽油脂肪酸组成没有影响,对脂肪酸含量和皂化值有较小的影响。     

一种从红花油中制备高纯度亚油酸的方法

红花油中亚油酸含量可达73％～85％，是制取亚油酸的一种理想原料。本文以红花油为原料，对亚油酸的提取方法进行了研究，经皂化、酸解、尿素包合等工艺制备出了纯度高达99．65％的亚油酸，是实验室制取亚油酸的较佳方法。     

Single-laboratory validation of a saponification method for the determination of four polycyclic aromatic hydrocarbons in edible oils by HPLC-fluorescence detection

An analytical method is reported for the determination of four polycyclic aromatic hydrocarbons (benzo[a]pyrene (BaP), benz[a]anthracene (BaA), benzo[b]fluoranthene (BbF) and chrysene (CHR)) in edible oils (sesame, maize, sunflower and olive oil) by high-performance liquid chromatography. Sample preparation is based on three steps including saponification, liquid–liquid partitioning and, finally, clean-up by solid phase extraction on 2 g of silica. Guidance on single-laboratory validation of the proposed analysis method was taken from the second edition of the Eurachem guide on method validation. The lower level of the working range of the method was determined by the limits of quantification of the individual analytes, and the upper level was equal to 5.0 µg kg^?1. The limits of detection and quantification of the four PAHs ranged from 0.06 to 0.12 µg kg^?1 and from 0.13 to 0.24 µg kg^?1. Recoveries of more than 84.8% were achieved for all four PAHs at two concentration levels (2.5 and 5.0 µg kg^?1), and expanded relative measurement uncertainties were below 20%. The performance of the validated method was in all aspects compliant with provisions set in European Union legislation for the performance of analytical methods employed in the official control of food. The applicability of the method to routine samples was evaluated based on a limited number of commercial edible oil samples.     

Improving Extraction of Lutein from Egg Yolk Using an Ultrasound-Assisted Solvent Method

ABSTRACT:  Extraction yields of lutein from egg yolk using both hexane solvent (SOL) and ultrasound-assisted solvent (UA-SOL) extraction methods at different levels of saponification were compared. The yields obtained with SOL and UA-SOL were significantly different. The broad range of extraction yield in the SOL method at different levels of saponification was from 6.3 to 63.8 μg/g. Compared to the SOL method, the extraction yield using UA-SOL was significantly higher at each corresponding saponification level. The yield of the UA-SOL method without alkaline solution was the highest (89.9 μg/g) of all. The yield of the UA-SOL decreased as the level of saponification increased. The results indicated that alkaline significantly affected stability of lutein in egg yolk and resulted in underestimation of its concentration. Compared with the traditional saponification solvent extraction method, the UA-SOL extraction method was more effective in extracting lutein from the sample matrix, and presumably by avoiding degradation reactions.     

皂化值法定量分析烷醇酰胺

通过测定皂化值和游离胺含量，对油酸单乙醇酰胺产品的纯度进行了定量分析，给出了酰胺和氨基酯含量的计算公式，并与红外光谱进行了比较，结果基本一致．     

微藻总脂含量快速测定的方法比较

快速、可靠、简便的总脂含量测定方法在富油藻种筛选、功能性藻油评估及微藻生物学研究中至关重要。本研究以三种微藻(微绿球藻Nannochloris sp.、普通小球藻Chlorella vulgaris、绿色巴夫藻Pavlova viridis)藻粉为原料,系统比较了四种方法(Bligh-Dyer法、改良Bligh-Dyer法、ASTM标准法和皂化法)用于测定微藻中总脂含量的差异,并以原位转酯法为对照,进一步分析了各方法总脂提取物中的脂肪酸含量及组成。改良Bligh-Dyer法和ASTM标准法总脂测定结果稳定,脂肪酸回收率最高,三种藻粉中分别为93.65%和93.74%、85.02%和85.77%、88.62%和88.84%;两者总脂含量及提取物中脂肪酸的组成和含量均无显著差异(p0.05)。显然,改良Bligh-Dyer法操作简便、分析时间短(1 h)、所需样品量少(0.25 g),可替代ASTM标准法,作为实验室快速准确测定微藻总脂含量的首选方法。     

皂化法精制粗米糠蜡的研究

糠蜡是由高级脂肪酸和高级一元醇所组成的酯类混合物,是一种多用途的化工原料。文章通过皂化法对精制粗米糠蜡的皂化温度、加入碱液浓度及皂化时间三个操作因素进行考察,以产品得率为指标找出最优的工艺条件。实验结果表明：三个操作因素对产品得率影响主次顺序为皂化温度、皂化时间、碱浓度;产品得率的最佳工艺条件为皂化温度95℃,皂化时间3．5h,加入碱液浓度6％,精制米糠蜡的收率75.3％。     

几种食用油中不饱和脂肪酸和皂化值的测定研究

以茶籽油、玉米油、橄榄油、芝麻油、花生油为原料,利用容量分析方法测定其不饱和脂肪酸含量及皂化值.经碘酊法测定,这5种食油用的不饱和脂肪酸含量(以碘值衡量)最高的为茶籽油,达95.46g·(100g)-1,碘值最低的为花生油54.67g·( 100g)-1.这5种植物油碘值由大至小依次为:茶籽油＞玉米油＞橄榄油＞芝麻油＞...     

Optimization and development of a SPE-HPLC-UV method to determine astaxanthin in Saccharina japonica

Abstract: An effective and accurate method including extraction, saponification, and separation was developed to determine astaxanthin (AX) in Saccharina japonica. The optimal extraction conditions with different solvents were investigated. 29.30 μg/g of AX was extracted from dry Saccharina japonica powder by solvent. After subsequent saponification, the extracted amount of AX was increased to 37.26 μg/g. Furthermore, 3 different ionic liquid‐based silicas were prepared as sorbents for the solid phase extraction of AX from the extract. By comparing the adsorption isotherms of AX on different ionic liquid‐based silicas, suitable sorbent was successfully selected and applied for separation of AX from extract. Practical Application: Astaxanthin, in 3 main forms (free, monoesters, and diesters), can be obtained from marine plants and animals. By extraction with subsequent saponification, the astaxanthin was extracted from Saccharina japonica. And then, ionic liquid‐based silicas were used to separate the astaxanthin from the extract solution. This method can be widely applied for determination, or even industrial separation and purification of astaxanthin from many other algae.